LAUSR

INTRODUCTION Medicare eligibility at 65 has been associated with increased diagnosis and survival for certain cancers due to greater health care utilization. We aim to assess for a similar "Medicare effect" for bladder and kidney cancers, which has not been previously established. METHODS Patients diagnosed with bladder or kidney cancer from 2000-2018 at ages 60-69 years were identified with the Surveillance, Epidemiology, and End Results database. We used age-over-age percent change calculations to characterize trends in cancer diagnoses focusing on patients aged 65. Multivariable Cox models were used to compare cancer-specific mortality across ages at diagnosis. RESULTS We identified 63,960 patients diagnosed with bladder cancer and 52,316 diagnosed with kidney cancer. Age-over-age change in diagnosis was highest for patients aged 65 compared to all other ages for both cancers (P < .01 for both). Stratified by stage, patients aged 65 had a higher age-over-age change than those aged 61-64 or 66-69 for in situ (P = .01, P < .01, respectively), localized (P = .03, P = .01), and regional (P = .02, P = .02) bladder cancer and localized (P = .01, P = .01) kidney cancer. Bladder cancer patients aged 65 had lower cancer-specific mortality than patients aged 66 (HR = 1.17, P = .01) and 69 (HR = 1.18, P = .01), while kidney cancer patients aged 65 had lower mortality than patients aged 64 (HR = 1.18, P < .01) and 66-69. CONCLUSIONS The age of 65, marking the onset of Medicare eligibility, is associated with more diagnoses of bladder and kidney cancer. Patients diagnosed at age 65 demonstrate decreased bladder and kidney cancer-specific mortality.